You find that compiling a Theano function is taking too much time? You
can get profiling information about Theano optimization. The normal
:ref:`Theano profiler <tut_profiling>` will provide you with very high
level information. The indentation show the included in/subset
relationship between sections. The top of its output look like this:
.. code-block:: none
Function profiling
==================
Message: PATH_TO_A_FILE:23
Time in 0 calls to Function.__call__: 0.000000e+00s
Total compile time: 1.131874e+01s
Number of Apply nodes: 50
Theano Optimizer time: 1.152431e+00s
Theano validate time: 2.790451e-02s
Theano Linker time (includes C, CUDA code generation/compiling): 7.893991e-02s
Import time 1.153541e-02s
Time in all call to theano.grad() 4.732513e-02s
Explanations:
* ``Total compile time: 1.131874e+01s`` give the total time spend in inside `theano.function`.
* ``Number of Apply nodes: 50`` mean that after optimization, there is 50 apply node in the graph.
* ``Theano Optimizer time: 1.152431e+00s`` mean that we spend 1.15s in the ``theano.function`` phase where we optimize(modify) the graph to make it faster/more stable numerically/work on GPU/...
* ``Theano validate time: 2.790451e-02s`` mean that we spend 2.8e-2s in the validate subset of the optimization phase.
* ``Theano Linker time (includes C, CUDA code generation/compiling): 7.893991e-02s`` mean that we spend 7.9e-2s in the ``theano.function`` linker phase.
* ``Import time 1.153541e-02s`` is a subset of the linker time where we import the compiled module.
* ``Time in all call to theano.grad() 4.732513e-02s`` tell that we spent a total of 4.7e-2s in all calls to theano.grad. This is outside call to ``theano.function``.
The linker phase include the generation of the C code, the time spent
by g++ to compile and the time needed by Theano to build the object we
return. The C code generation and compilation is cached, so the first
time you compile a function and the following one could take different
amount of execution time.
Detailed profiling of Theano optimizer
--------------------------------------
You can get more detailed profiling information about the Theano
optimizer phase by setting to `True` the Theano flags
:attr:`config.profile_optimizer`.
This will output something like this:
.. code-block:: none
Optimizer Profile
-----------------
SeqOptimizer OPT_FAST_RUN time 1.152s for 123/50 nodes before/after optimization
